Since taking the helm at the newsagent, Ms Swann has focused on tightly controlling costs; expanding Smith 's travel unit; and moving the company away from low–margin entertainment products and towards stationery.

Despite turbulence on the high street, Ms Swann has therefore managed to protect margins and expand profits.

Turnover was on the decline. Against a tough economic backdrop, like–for–like sales at the high street business fell 5pc in the half year and at the travel division – which operates in airports, railway stations and motorway service areas – like–for–like sales fell 4pc.

However, trading profits in travel were up 7pc and on the high street they rose 2pc. The latter was partly down to finding £9m of cost savings during the first half of the year, with a further £8m already identified for the second half.

Among the cost–saving measures are new tills, which are more energy efficient, faster and have lower maintenance costs. The thrifty chain is also testing measures such as adding time clocks to its in–store chillers.

"The drivers of growth have been the usual combination of sales down, gross margin up, costs down and cash generation enabling share buy–backs," added the analyst, who has a "hold" rating on Smith .

This familiar formula of finding cost savings and moving away from low–margin goods to protect the bottom line has pleased the City.

When Ms Swann took control of the company in 2003, the shares were hovering around 250p. Yesterday, they were up 48.5p at 793.5p.

That is quite some legacy for the chief executive, who last October announced her intention to bow out this year after a decade at Smith . She will be replaced by Steve Clarke at the beginning of July.

Although Smith has emerged as one of the high street winners, in January, Questor moved the company from a "buy" to a "hold" on valuation grounds.

At that point, the shares were trading at 650p; they have since risen another 20pc.

Smith 's prospective yield is a decent 3.9pc, rising to 4.2pc next year; and the shares are trading on a 2013 earnings multiple of 11.32, falling to 10.4.

With the earnings multiple rather punchy, Questor still says hold for now.